package com.atguigu.flink.chapter07.state;

import com.atguigu.flink.bean.WaterSensor;
import org.apache.flink.api.common.state.ValueState;
import org.apache.flink.api.common.state.ValueStateDescriptor;
import org.apache.flink.configuration.Configuration;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.functions.KeyedProcessFunction;
import org.apache.flink.util.Collector;

/**
 * @Author lizhenchao@atguigu.cn
 * @Date 2021/9/18 15:34
 */
public class Flink04_State_Keyed_Value {
    public static void main(String[] args) throws Exception {
        StreamExecutionEnvironment env = StreamExecutionEnvironment
            .getExecutionEnvironment()
            .setParallelism(3);
        env
            .socketTextStream("hadoop162", 9999)
            .map(value -> {
                String[] datas = value.split(",");
                return new WaterSensor(datas[0], Long.valueOf(datas[1]), Integer.valueOf(datas[2]));
                
            })
            .keyBy(WaterSensor::getId)
            .process(new KeyedProcessFunction<String, WaterSensor, String>() {
                
                private ValueState<Integer> lastVcState;
                
                
                @Override
                public void open(Configuration parameters) throws Exception {
                    lastVcState = getRuntimeContext()
                        .getState(new ValueStateDescriptor<Integer>("lastVcState", Integer.class));
                }
                
                @Override
                public void processElement(WaterSensor value,
                                           Context ctx,
                                           Collector<String> out) throws Exception {
                    Integer lastVc = lastVcState.value();
                    if (lastVc != null) {
                        if (value.getVc() > 10 && lastVc > 10) {
                            out.collect(ctx.getCurrentKey() + " 连续两次水位超过10, 红色预警...");
                        }
                    }
                    lastVcState.update(value.getVc());
                }
            })
            .print();
        
        env.execute();
        
    }
}
